Kerry Bazany: Feeding livestock seaweed?

[Global] Cows and sheep are some of my very favorite animals. They are cute, docile, and conjure up childhood memories of delight seeing them on our family trips to the “country”, aka Westchester County, New York, just north of the gritty, noisy confines of our apartment in the Bronx. But to be honest, cows and sheep can offend the senses: they burp, and fart, a lot. It is precisely because of such indelicate bovine habits that scientists are now pondering how to reduce livestock “emissions” in order to help our planet.

Adding Seaweed to Cattle Feed Could Cut Methane Emission by More Than 70 Percent

Scientists have discovered that adding dried seaweed to both sheep and cattle feed, methane emissions could be reduced by more than 70 percent. Methane has 36 times the global warming potential of carbon dioxide (CO2). Much of the media is saturated with dire warnings about CO2 emissions; however, the release of methane gas is far more concerning. Until I researched this topic, I was not aware of the impact of methane, and I was surprised. Cows and sheep release 3.1 gigatonnes via their burps and farts! A gigatonne is used to describe something gigantic: one gigatonne is equivalent to one billion parts. To put this in perspective, if we cut that rate by 70 percent by adding seaweed to livestock feed, we’d be eliminating 2.17 gigatonnes that are released into the atmosphere each year. That is approximately the amount of CO2 that India produces each year.

Much of the current research regarding this potentially beneficial procedure comes from Queensland where Professor of Aquaculture Rocky De Nys at James Cook University in Townsville has been studying the effects seaweed consumption can have on cow’s methane production. De Nys and his team discovered that just a small amount of seaweed added to a cow’s diet can reduce methane emissions by more than 99 percent. Most of the methane that is emitted comes by way of the front end of the cow by way of burping as opposed to what you may think (farting).

It all started with a dairy farmer in Canada by the name of Joe Dorgan who inadvertently discovered that the cows that were grazing on washed-up seaweed by the shore were more productive and healthier than their counterparts who did not ingest the seaweed. He began to feed his herd a mixture including storm-tossed seaweed and saw impressive results with the size, health, and reproductive activity of the cattle, or in a rather colorful colloquial expression, “rip-roaring heats!” In 2014, Canadian researchers Rob Kinley and Alan Fredeen confirmed Dorgan’s results, and not long after, Professor De Nys joined in the research in Australia.

Cow Farts and Burps are no Laughing Matter

CO2 emissions have long been the culprit and perhaps scapegoat of the ongoing politically-charged discussions on climate change. That is not to diminish the enormous contribution CO2 generates in our atmosphere as a significant factor in global warming, but perhaps increased emphasis and research needs to be conducted in methane emissions and their impact on our atmosphere.

Methane is approximately 25 times more potent than carbon dioxide over the course of a 100 year time span. A single cow releases between 70 and 120 kilograms of methane per year, with cow burps accounting for 26 percent of the US’s total methane emissions. As a matter of fact, the US is only the world’s fourth largest producer of cattle behind China, Brazil, and India. The cows that currently roam our planet number about 1.5 billion! In order to help individuals understand and possibly visualize this type of impact from methane, scientists have developed a GWP (Global Warming Potential) based upon two factors: their ability to absorb energy, and how long they remain in the atmosphere.

For example, CO2 has a GWP of 1, and scientists have averaged this out across its lifespan in Earth’s climate that lasts for thousands of years. By contrast, methane has a GWP of 28 to 36 over its first 100 years in Earth’s climate system, meaning methane’s lifetime is much shorter than CO2’s, but methane is better at trapping radiation in our delicate atmosphere. Recently, a report from the Intergovernmental Panel on Climate Change discovered that during its first 20 years in the atmosphere, methane has a GWP of 86, meaning it has the capacity to warm the planet 86 times as much as carbon dioxide.

So How Does the Seaweed Consumption Work and is it Sustainable?

Researchers have discovered that all seaweed is not alike when it comes to adding it to cattle feed. A specific type of red algae called Asparagopsis Taxiformis grows off the coast of Queensland, Australia, and is the type of seaweed that greatly reduced cattle methane production, by as much as 99 percent. Additionally, it only required a dose of approximately 2 percent in order to work effectively. When the cow ingests these algae, it produces a compound called Bromoform (CHBR3) that interacts with the enzymes in the cow’s stomachs and inhibits the cycle of methane production before it can be released into the atmosphere.

Unfortunately, there is a caveat, or a bump in the proverbial road, when it comes to what seems to be almost a “cure” for our ailing atmosphere. The seaweed that performs the best is a species of algae called Asparagopsis Taxiformis, as mentioned above, and it is native to Australia. In order to provide quantities of the seaweed to just Australia’s cattle population, commercial cultivation of over 15,000 acres of seaweed would be necessary. Harvesting on a farm by farm basis would be possible, but probably not feasible on a large scale.

The primary obstacle with this seemingly exciting and fascinating method lies in the practicality of delivering huge amounts of seaweed via commercial farming to millions of cows. But like other barriers to the implementation of beneficial practices, we will hopefully find a way.